Kevin Winter/Getty ImagesYou’re in charge of a live, three-hour awards telecast and two of your performers bail out. What do you do? Find out Friday night during Grammys Greatest Stories: A 60th Anniversary Special.

The show features behind-the-scenes looks at memorable Grammy performances — including that night in 2009 when Chris Brown and Rihanna pulled out of the show at the last minute, without explanation. Of course, that was the night Brown assaulted Rihanna.

“We were about an hour into our dress rehearsal the day of the show when we got two separate calls, one from Rihanna’s people and one from Chris Brown’s people, saying they weren’t coming,” Grammy producer Ken Ehrlich tells ABC Radio. “We didn’t know anything more than that at the time, but…we just had to act.”

Ehrlich grabbed Justin Timberlake and, he says, “went down a list of people who were presenting that night and Al Green was one of them. So we got him out of the [bathtub] in his hotel…and he came over and rehearsed, and we added Keith Urban and Boyz II Men.”

“Within three hours, there was a segment…that didn’t exist four or five hours before that,” says Ehrlich. You’ll see that performance on the special, and hear Justin talk about it, too.